Spring Boot Actuator for Apache Geode & VMware Tanzu GemFire

@Data
@Region("TemperatureReadings")
@RequiredArgsConstructor(staticName = "newTemperatureReading")
@SuppressWarnings("unused")
public class TemperatureReading {

	private static final int BOILING_TEMPERATURE = 212;
	private static final int FREEZING_TEMPERATURE = 32;

	@Id
	private Long timestamp = System.currentTimeMillis();

	@NonNull
	private final Integer temperature;

	@Transient
	public boolean isBoiling() {

		Integer temperature = getTemperature();

		return temperature != null && temperature >= BOILING_TEMPERATURE;
	}

	@Transient
	public boolean isFreezing() {

		Integer temperature = getTemperature();

		return temperature != null && temperature <= FREEZING_TEMPERATURE;
	}

	@Transient
	public boolean isNormal() {
		return !(isBoiling() || isFreezing());
	}

	@Override
	public String toString() {
		return String.format("%d °F", getTemperature());
	}
}

public class TemperatureEvent extends ApplicationEvent {

	@Getter
	private final TemperatureReading temperatureReading;

	public TemperatureEvent(Object source, TemperatureReading temperatureReading) {

		super(source);

		this.temperatureReading = temperatureReading;
	}
}

public interface TemperatureReadingRepository extends CrudRepository<TemperatureReading, Long> {

	List<TemperatureReading> findByTimestampGreaterThanAndTimestampLessThan(
		Long timestampLowerBound, Long timestampUpperBound);

	@Query("SELECT count(*) FROM /TemperatureReadings WHERE temperature >= 212")
	Integer countBoilingTemperatureReadings();

	@Query("SELECT count(*) FROM /TemperatureReadings WHERE temperature <= 32")
	Integer countFreezingTemperatureReadings();

}

@Service
@SuppressWarnings("unused")
public class TemperatureMonitor {

	private final ApplicationEventPublisher applicationEventPublisher;

	public TemperatureMonitor(ApplicationEventPublisher applicationEventPublisher) {

		Assert.notNull(applicationEventPublisher, "ApplicationEventPublisher is required");

		this.applicationEventPublisher = applicationEventPublisher;
	}

	@ContinuousQuery(name = "BoilingTemperatureMonitor",
		query = "SELECT * FROM /TemperatureReadings WHERE temperature >= 212")
	public void boilingTemperatureReadings(CqEvent event) {

		Optional.ofNullable(event)
			.map(CqEvent::getNewValue)
			.filter(TemperatureReading.class::isInstance)
			.map(TemperatureReading.class::cast)
			.map(it -> new BoilingTemperatureEvent(this, it))
			.ifPresent(this.applicationEventPublisher::publishEvent);
	}

	@ContinuousQuery(name = "FreezingTemperatureMonitor",
		query = "SELECT * FROM /TemperatureReadings WHERE temperature <= 32")
	public void freezingTemperatureReadings(CqEvent event) {

		Optional.ofNullable(event)
			.map(CqEvent::getNewValue)
			.filter(TemperatureReading.class::isInstance)
			.map(TemperatureReading.class::cast)
			.map(it -> new FreezingTemperatureEvent(this, it))
			.ifPresent(this.applicationEventPublisher::publishEvent);
	}
}

@Service
@SuppressWarnings("unused")
public class TemperatureSensor {

	private final PrimitiveIterator.OfInt temperatureStream =
		new Random(System.currentTimeMillis())
			.ints(-100, 400)
			.iterator();

	private final TemperatureReadingRepository repository;

	public TemperatureSensor(TemperatureReadingRepository repository) {

		Assert.notNull(repository, "TemperatureReadingRepository is required");

		this.repository = repository;
	}

	@Scheduled(fixedRateString = "${example.app.temp.sensor.reading.schedule.rate:1000}")
	public void readTemperature() {

		TemperatureReading temperatureReading =
			TemperatureReading.newTemperatureReading(temperatureStream.nextInt());

		this.repository.save(log(temperatureReading));
	}

	private TemperatureReading log(TemperatureReading temperatureReading) {

		PrintStream out = temperatureReading.isNormal() ? System.out : System.err;

		out.printf("TEMPERATURE READING [%s]%n", temperatureReading);

		return temperatureReading;
	}
}

@Region("TemperatureReadings")
public class TemperatureReading { ... }

@SpringBootApplication
@CacheServerApplication(name = "TemperatureServiceServer")
@EnableEntityDefinedRegions(basePackageClasses = TemperatureReading.class)
@EnableGemfireRepositories(basePackageClasses = TemperatureReadingRepository.class)
@EnableScheduling
@EnableStatistics
@UseGroups("TemperatureSensors")
@SuppressWarnings("unused")
public class BootGeodeServerApplication {

	public static void main(String[] args) {

		new SpringApplicationBuilder(BootGeodeServerApplication.class)
			.web(WebApplicationType.SERVLET)
			.build()
			.run(args);
	}

	@Bean
	TemperatureSensor temperatureSensor(TemperatureReadingRepository repository) {
		return new TemperatureSensor(repository);
	}

	@Bean
	RegionConfigurer temperatureReadingsConfigurer() {

		return new RegionConfigurer() {

			@Override
			public void configure(String beanName, PeerRegionFactoryBean<?, ?> regionBean) {

				Optional.ofNullable(beanName)
					.filter("TemperatureReadings"::equals)
					.ifPresent(it -> regionBean.setStatisticsEnabled(true));
			}
		};
	}

	@Bean
	@DependsOn("TemperatureReadings")
	IndexFactoryBean temperatureReadingTemperatureIndex(GemFireCache gemfireCache) {

		IndexFactoryBean temperatureTimestampIndex = new IndexFactoryBean();

		temperatureTimestampIndex.setCache(gemfireCache);
		temperatureTimestampIndex.setExpression("temperature");
		temperatureTimestampIndex.setFrom("/TemperatureReadings");
		temperatureTimestampIndex.setName("TemperatureReadingTemperatureIdx");

		return temperatureTimestampIndex;
	}

	@Bean
	@DependsOn("TemperatureReadings")
	IndexFactoryBean temperatureReadingTimestampIndex(GemFireCache gemfireCache) {

		IndexFactoryBean temperatureTimestampIndex = new IndexFactoryBean();

		temperatureTimestampIndex.setCache(gemfireCache);
		temperatureTimestampIndex.setExpression("timestamp");
		temperatureTimestampIndex.setFrom("/TemperatureReadings");
		temperatureTimestampIndex.setName("TemperatureReadingTimestampIdx");

		return temperatureTimestampIndex;
	}
}

@SpringBootApplication
@EnableClusterAware
@EnableEntityDefinedRegions(basePackageClasses = TemperatureReading.class)
@UseGroups("TemperatureMonitors")
@UseMemberName("TemperatureMonitoringService")
@SuppressWarnings("unused")
public class BootGeodeClientApplication {

	public static void main(String[] args) {

		new SpringApplicationBuilder(BootGeodeClientApplication.class)
			.web(WebApplicationType.SERVLET)
			.build()
			.run(args);
	}

	@Bean
	TemperatureMonitor temperatureMonitor(ApplicationEventPublisher applicationEventPublisher) {
		return new TemperatureMonitor(applicationEventPublisher);
	}

	@EventListener(classes = { BoilingTemperatureEvent.class, FreezingTemperatureEvent.class })
	public void temperatureEventHandler(TemperatureEvent temperatureEvent) {

		System.err.printf("%1$s TEMPERATURE READING [%2$s]%n",
			temperatureEvent instanceof BoilingTemperatureEvent ? "HOT" : "COLD",
				temperatureEvent.getTemperatureReading());
	}
}